I would like a transparent roadmap of content they are actively working on. I don't even need a timeline, would just be nice to know that someone is aware and is working on things that the community has contentions with. I may not agree with all of it, but everyone has a different experience and while not all feedback is good, all of it is important.
Dark Knight is in a sorry state and should be reworked for PvP as well as PvE (way too strong in PvP and too weak/gutted play style in PvE). Tanks shouldn't be invincible against bosses and rather than nerf tanks or remove their utility, just buff the damage that bosses inflict with auto attacks in normal content. Healers in normal content now have a little more to do and I like that but I rarely have a reason to look at my tank's health. I like the changes made to jobs overall but I'm very curious to see what they're planning for future progression. I don't think it would be a bad idea at this point to revisit the Class/Job system and consider making alternate jobs/specializations for progression past 100, it could be an interesting way to add Jobs in the future without needing to design a totally new weapon and gear set for them.
I've wondered if the solution to this isn't reworking how level sync works. It would be a massive change, but I think if people didn't feel like they lost half of their job when they got synced down, SE might not have such a hard time getting players in to older content, or helping new players get through the story. It couldn't hurt to look at a few jobs and consider how their skills are dispersed through levels, too, maybe introduce some job-specific mechanics earlier.
It's problematic to view it as tedious, though. There is more content to go through before new players can get caught up, but those new players will be experiencing the game and story for the first time. They don't need a way for players to catch up more quickly, they just need to make it more worthwhile and enjoyable for all players to go through that old content so that there is no feeling of a great chasm between new players and old. PvP is an example where this doesn't need to matter. In theory, zones like Eureka and Bozja, or even deep dungeons, don't need to be restrictive to who can enter, either. Gold Saucer doesn't care about progression. They could build on these foundations they laid a long time ago and it would go a long way.